Welcome back to The Hollywood Reporter's weekly DC TV Watch, a rundown of all things DC Comics on the small screen. Every Saturday, we round up the major twists, epic fights, new mysteries and anything else that goes down on The CW's Arrow, The Flash, Legends of Tomorrow, Supergirl and Black Lightning, and Fox's Gotham. Note: The Flash, Arrow, Gotham, Legends of Tomorrow and Black Lightning have wrapped for the season.
Supergirl season three finale
Turn back time | In an extremely action-packed finale, Supergirl effectively tied up all the loose ends of the season. Kara (Melissa Benoist) was convinced by her team at the DEO to throw out her "no killing" rule when it came to Reign (Odette Annable), but it cost her dearly. As Reign was dying thanks to an assist from a newly-superpowered Sam (also Annable) wielding Reign's own sword, Reign used her laser vision to instantly kill Sam, Alura (Erica Durance) and Mon-El (Chris Wood). A shell-shocked Kara looked around in her "victory" to see her family and loved ones laying dead on the ground, and she immediately broke down. She blamed herself for doubting her morals and her code because she let others convince her to kill Reign. It was a chill-inducing moment as Kara floundered under the horror of what had just happened, but the Girl of Steel didn't wallow. She immediately picked up Mon-El's Legion ring and traveled back in time without a second thought to the consequences. She went back to the moment where Sam was about to help her kill Reign, and instead took Reign and Sam with her to the Dark Valley. Sam was then able to overcome her darker alter ego and forced Reign to drink water from the Fountain of Lilith, effectively trapping her there forever. When Mon-El pulled them out of the Dark Valley with a jolt of electricity, Reign was gone, Sam was somehow completely human and Kara was proud to have upheld her values of no killing.
Saying goodbye | But in the midst of all the action, there were a lot of character exits in this week's finale. M'yrnn (Carl Lumbly) sacrificed himself to save the planet from becoming terraformed into New Krypton by Reign. Before he died, he shared a heart wrenching goodbye with his son J'onn (David Harewood), bringing their emotional father-son storyline to a close. Mon-El realized he was needed in the future, effectively putting an end to any fantasy he held about staying in the present with Kara and rekindling their relationship. He went back to the 31st century to continue leading the Legion (and Wood is not returning to the series next season), but before he left the Legion made a swap. Brainiac 5 (Jesse Rath) stayed behind because his "distant relative" was saved from the blight, and this evil relative created a new virus that kills all A.I.'s in the future. Brainy stayed at the DEO for his own safety, and offered Winn (Jeremy Jordan) his place in the Legion as the resident genius. After debating whether or not to leave his home and friends for the future, Winn accepted (which explains his reduced role next season as he travels to the future).
Changes are coming | The last half of this week's finale laid some major groundwork for season four. J'onn decided to take his father's final words of wisdom to heart and left the DEO to live among the people of Earth. After donning a classy hat, he disappeared into the crowds of National City. Before he left, he handed the reins of the DEO over to Alex (Chyler Leigh), who had just tried to quit in order to become a mother (via adoption). Now Alex will step down from being in the field for the "much safer" position of the head of the DEO, and thereby not putting herself in so much danger so she can be a responsible mother at some point in the future. Mon-El and Winn left with Imra (Amy Jackson) for the future. James (Mehcad Brooks) revealed publicly that he is Guardian. Alura left with the black rock to return to Argo City believing that all the rock was leaving Earth with her, but Lena (Katie McGrath) secretly manufactured more of it to test. She began "phase two" without realizing how unpredictable it truly is. Because ...
Seeing double | When Kara previously used the black rock 48 hours earlier to travel to the Dark Valley with Reign and Sam, it sent a mysterious smoke trail across the world to Siberia, where it created a clone of Kara. In the final scene of the episode, the clone came to, naked and confused, and approached a military camp before the credits rolled. If the black rock can make a second Supergirl, there's no telling what Lena is about to accidentally do with it back in National City.
Burning questions for Supergirl season four
Is the black rock really black kryptonite? | No one has actually uttered the words "black kryptonite" on Supergirl, and yet the latter half of this season and presumable a large chunk of next season focuses a lot on this alien black rock that powers Argo City. Seeing as how black kryptonite separates the personalities of a single being into two separate beings, and the black rock either split Kara into two or cloned her, it's highly likely it is black kryptonite. That means that the Kara relaxing on the couch with Alex at the end of the episode isn't fully herself, as the darker parts of her personality may have been split from her to create the imposter. That explains why, despite losing so many friends, Kara was so cheerful at the end of the finale. Another clue that this is black kryptonite is the fact that Lena was able to create more of it, as black kryptonite is created by heating green kryptonite to extremely high temperatures.
How much is Supergirl going Red Son for season four? | When the black kryptonite split Kara into two beings and one arrived confused and naked in Siberia, it was clear that Supergirl was steering in the direction of famous comic book run Red Son for season four. But since that storyline asks, "what if Superman had been raised in the Soviet Union instead of the United States," there are some major tweaks that will have to be made to tailor it to Supergirl. The series isn't turning back the clock to see what the world would be like if Kara grew up in Russia, but rather introducing a second Supergirl in Russia. So will this be like The Flash taking on Flashpoint for only one episode and then following the ramifications for the rest of the season? And since the second Supergirl is most likely split from Kara and is the darker aspects of her personality, will this be more like a Bizarro Supergirl than an alternate universe Supergirl? There are many different facets of comic book source material being drawn from for next season, and how the writers take it from here is anyone's guess.
What kind of consquences will Supergirl face for changing the timeline? | As Barry (Grant Gustin) has learned from the aformentioned Flashpoint, changing the timeline doesn't come without a price. Even though Kara went back only a minute in time, she still changed her actions and seriously altered the future, saving the lives of Alura, Mon-El and Sam. Will Supergirl follow through and teach Kara that messing with time travel isn't as simple as she thinks? Or is the black kryptonite splitting her into two the consequence?
How much will Winn be seen next season? | Winn traveling to the future came about because Jordan, a series regular since the beginning of the show, is going to be only recurring next season and Supergirl had to figure out a way to explain his diminished appearances. Jordan took to his Instagram to explain his exit as a series regular, but some questions about his future on the show remain. Does this mean he'll pull a Cat Grant (Calista Flockhart) and only appear in premieres and finales before eventually disappearing from the series altogether? Or will he actually pop in here and there as Winn time travels with different Legion members and reunites with the DEO when they need help? And how long will it take Winn to design new Legion uniforms?
The Flash
Sticking around | This shouldn't come as a surprise to any Flash fans, but Jessica Parker Kennedy has been promoted to series regular for the upcoming season five, The Hollywood Reporter has learned. As her "mystery girl" character finally revealed in the season four finale that she is Barry (Grant Gustin) and Iris' (Candice Patton) speedster daughter from the future and she screwed up the timeline, expect season five to fully dive into Nora West-Allen's history and her mistake. Barry might have learned his lesson with time travel but it seems that messing up the timeline runs in the family. Kennedy is repped by Luber Roklin Entertainment and Gersh Agency.
Gotham will return for season five on Fox. Supergirl will return for season four, The Flash will return for season five, Arrow will return for season seven, Legends of Tomorrow will return for season four and Black Lightning will return for season two, all on The CW.
Supergirl